STMicroelectronics STA508

Overview

STA508 from STMicroelectronics is a monolithic quad half-bridge power stage in Multipower BCD technology, designed as the output stage for stereo all-digital DDX™ amplifiers. It delivers 80 + 80 W @ THD = 10% into 8 Ω at VCC = 35 V (dual bridge), or 160 W peak @ THD = 10% into 4 Ω (single BTL), with 200 mΩ RdsON, thermal warning output, and undervoltage protection.

For engineers reviewing the STA508 datasheet, STA508 pinout, STA508 application, or STA508 equivalent, this device supports reconfigurable bridge topologies (dual, single BTL, or binary half-bridge), features CMOS-compatible logic inputs with VL-referenced thresholds, and integrates thermal/UV/fault protections critical for high-efficiency audio power stages.

Technical Context

The STA508 implements four independent complementary DMOS half-bridges with matched P/N-channel RdsON (95% matching), dynamic dead-time control (50 ns at 4 A), and input logic referenced to VL voltage (0.8–1.7 V high/low thresholds at VL = 3.3 V). Its CONFIG pin enables topology reconfiguration without external hardware changes.

Thermal management includes an open-collector TH_WAR pin asserting low at 130 °C junction temperature and integrated thermal shutdown. Protection logic combines undervoltage lockout (7 V threshold), short-circuit current limiting (4.5–9 A), and fault reporting via open-collector FAULT pin.

Key Specifications

Pinout & Package

STA508 uses the PowerSO-36 (EPU) package with exposed thermal pad up - optimized for high-power audio applications requiring efficient heat transfer to heatsink via top-side mounting.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad half-bridge power stage applications.

Compared with TAS5381A and IRS2092S, STA508 uniquely integrates topology reconfiguration, thermal warning, and protection logic in a single PowerSO-36 package - reducing component count by ≥7 parts and eliminating external fault-handling circuitry.

Availability

STA508 is available at Aetrix Electronics and suitable for home audio amplifiers, automotive infotainment systems, and professional DSP amplifier modules requiring stable component supply and long-term industrial availability.

Supply support for STA508 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in power management, analog, MEMS, and microcontroller technologies for industrial, automotive, and consumer markets.

The STA508 belongs to ST's DDX™ audio power stage product line, engineered specifically for high-efficiency all-digital Class-D amplification with integrated protection and flexible topology configuration.

FAQ

What is the function of the CONFIG pin on STA508?

The CONFIG pin selects operating topology: grounded for standard quad half-bridge mode; tied to Vdd (Pins 21/22) to enable single BTL mode (OUT1A=OUT1B, OUT2A=OUT2B) for doubled current capability. This reconfiguration requires no external components and is validated per DS3503 Rev 6 Section 2.

How does the TH_WAR pin behave under thermal stress?

TH_WAR is an open-collector output that pulls low when junction temperature reaches 130 °C, providing early thermal warning before shutdown occurs. It remains low until temperature drops below hysteresis threshold (~120 °C), and requires an external pull-up resistor to Vdd for proper logic-level signaling.

Can STA508 drive 4 Ω loads in dual-bridge mode?

Yes - in dual full-bridge configuration, STA508 delivers 80 W per channel into 4 Ω at THD = 10% and VCC = 35 V, verified in DS3503 Rev 6 Figure 7 and Table 5. Thermal derating must be applied above 70 °C case temperature due to 50 W max dissipation limit.

What is the purpose of the VL pin?

VL sets the reference voltage for input logic thresholds (V_IN-HIGH = VL/2 + 300 mV, V_IN-LOW = VL/2 − 300 mV), enabling compatibility with 2.7–5 V logic supplies. It is not a power rail but a precision reference node - decoupling with 100 nF ceramic capacitor is mandatory per DS3503 Section 4.